---
name: "mount.posixovl"
section: "8"
platform: "linux"
package: "fuse-posixovl"
version: "1.3-1.1"
release: "Debian 13 (Trixie)"
platforms: ["linux"]
url: "https://new.carta.tech/mount.posixovl/8"
---

# mount.posixovl(8)

## NAME

posixovl -- FUSE file system that provides POSIX functionality

## SYNOPSIS

```
    mount.posixovl [-F] [-S SOURCE_DIR] TARGET_DIR [-- fuseopts]
```

## DESCRIPTION

If no source directory is given, the TARGET\_DIR specifies both source and target (mount point), yielding an "over mount".

Supports: chmod, chown, hardlink, mkfifo, mknod, symlink/readlink ACLs/xattrs (only in passthrough mode, no emulation).

## NOTES

Using posixovl on an already POSIX-behaving file system (e.g. XFS) incurs some issues, since detecting whether a path is POSIX behaving or not is difficult. Hence, the following decision was made:

```
    - permissions will be set to the default permissions (see below) unless
      a HCB is found that can override these
    - all lower-level files will be operated on/created with the user who
      initiated the mount
```

If no HCB exists for a file or directory, the default permissions are 644 and 755, respectively. The owner and group of the inode will be the owner/group of the real file.

Each non-regular, non-directory virtual file will have a zero-size real file. Simplifies handling, and makes it apparent the object exists when using other operating system.

Command [**df**(1)](/df/1.md) will show:

```
    $ df -Tah
    File System    Type    Size  Used Avail Use% Mounted on
    /dev/hda5     vfat    5.9G  2.1G  3.9G  35% /windows/D
    posix-overlay(/windows/D)
         fuse.posixovl    5.9G  2.1G  3.9G  35% /windows/D
```

## OPTIONS

- **-F**

  Option **-F** will disable permission and ownership checks that would be required in case you have a POSIX mount over VFAT. For example, where /vfat is vfat, and /vfat/xfs is a POSIX-behaving file system.

## EXAMPLES

In general, posixovl does not handle case-insensitivity of the underlying file system (in case of VFAT, for example). If you create a file *X0* on VFAT, it is usually lowercased to *x0*, which may break some software, namely X.org. In order to make VFAT behave more POSIX-like, the following mount options are recommended:

```
    mount -t vfat /dev/sda5 /mnt/vfat -o check=s,shortname=mixed
```

## ENVIRONMENT

None.

## FILES

None.

## SEE ALSO

**mount**(1) **umount**(1)

## AUTHORS

Program was written by Jan Engelhardt \<jengelh@users.sourceforge.net\>.

This manual page was written by Jari Aalto \<jari.aalto@cante.net\>, for the Debian GNU system (but may be used by others). Released under license GNU GPL version 2 or (at your option) any later version. For more information about license, visit \<http://www.gnu.org/copyleft/gpl.html\>.